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EP0260337A1 - Force-measuring device with an electromagnetic transducer - Google Patents

Force-measuring device with an electromagnetic transducer Download PDF

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Publication number
EP0260337A1
EP0260337A1 EP86112831A EP86112831A EP0260337A1 EP 0260337 A1 EP0260337 A1 EP 0260337A1 EP 86112831 A EP86112831 A EP 86112831A EP 86112831 A EP86112831 A EP 86112831A EP 0260337 A1 EP0260337 A1 EP 0260337A1
Authority
EP
European Patent Office
Prior art keywords
measuring device
sleeve
transducer
inner cone
screwing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP86112831A
Other languages
German (de)
French (fr)
Other versions
EP0260337B1 (en
Inventor
Peter Wolfer
Georges Schaffner
Jean-Jacques Schmid
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kistler Instrumente AG
Original Assignee
Kistler Instrumente AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kistler Instrumente AG filed Critical Kistler Instrumente AG
Priority to DE8686112831T priority Critical patent/DE3664166D1/en
Priority to EP86112831A priority patent/EP0260337B1/en
Priority to AT86112831T priority patent/ATE44318T1/en
Priority to JP62199668A priority patent/JPS6383627A/en
Priority to US07/098,206 priority patent/US4800760A/en
Publication of EP0260337A1 publication Critical patent/EP0260337A1/en
Application granted granted Critical
Publication of EP0260337B1 publication Critical patent/EP0260337B1/en
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/0004—Force transducers adapted for mounting in a bore of the force receiving structure
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/16—Measuring force or stress, in general using properties of piezoelectric devices
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/26—Auxiliary measures taken, or devices used, in connection with the measurement of force, e.g. for preventing influence of transverse components of force, for preventing overload

Definitions

  • the invention relates to a measuring device with an electromechanical transducer for measuring the force effects in a mechanically loaded machine part or the like. Which can be used in a bore in the machine part and can be non-positively clamped therein while simultaneously pretensioning the transducer.
  • Measuring devices with electromechanical transducers are known per se (US-A-4 412 456, DE-A-34 07 620). They are primarily used to record partial forces or material strains in a mechanically loaded machine part and provide an electrical signal that represents a measure of the force acting on the machine part. Thanks to their high sensitivity, piezoelectric transducers, in particular those with quartz crystal elements, are preferably used in such measuring devices, since they can also be used in places where only relatively small partial forces occur.
  • DE-A-34 07 620 describes a measuring device with a piezoelectric transducer which can be inserted into the bore of a machine part in the manner described above and clamped therein. It has two coaxially arranged, partially longitudinally slotted sleeves which are movable in the axial direction relative to one another and which are in the manner of a Interact with expansion plugs. For this purpose, a conical surface is provided at the end of the inner sleeve that is deeper in the bore and presses against the other sleeve. The inner sleeve has two plane-parallel surfaces in the area of the cone surface, between which the piezoelectric transducer is clamped.
  • the legs of the outer sleeve divided by longitudinal slots are spread as a result of the wedge effect on the conical surface, as a result of which the measuring device is non-positively fixed to the bore wall.
  • the piezoelectric transducer is prestressed between the flat surfaces on the legs of the inner sleeve divided by longitudinal slots.
  • the outer sleeve has a head, which is either intended to be placed on the outside of the machine part or comes to lie in an extension of the bore opening and serves as a counter bearing for a clamping nut.
  • this measuring device is relatively complicated and expensive in terms of material and manufacture. E.g. requires the mounting of the piezoelectric transducer plane-parallel surfaces on the inside of the inner sleeve.
  • the legs of the inner sleeve that have the flat surfaces must be very elastic and, for example, relatively long, the length of the longitudinal slots also determining the overall length of the measuring device.
  • the outer sleeve is to be made out of solid material because of the intended head.
  • the arrangement of the piezoelectric transducer between plane-parallel surfaces of the inner sleeve is disadvantageous in that a defined position of the line of action of the force to be introduced into the transducer can hardly be achieved. If this line of action is eccentric or at an oblique angle to the transducer axis, bending moments occur which may increase the mode of operation of the transducer Lich impair.
  • the relative position of the line of action of the force application depends on different dimensional tolerances.
  • the transducer has no defined position in the direction of the longitudinal axis of the measuring device, and on the other hand, the relative position of the two sleeves in the axial direction is not defined, which has the consequence in the design with the conical surface provided on the inner sleeve that the axial position of the Pressing the conical surface, the force on the inner sleeve causing the force of the outer sleeve can vary depending on the deviations from the target value of the relevant dimensions of the two sleeves in the cone area.
  • DE-A-34 07 620 also describes an embodiment in which a grub screw is provided as the threaded connection, which is screwed into an internal thread of the outer sleeve and presses on the inner sleeve to generate the axial clamping force.
  • a grub screw is provided as the threaded connection, which is screwed into an internal thread of the outer sleeve and presses on the inner sleeve to generate the axial clamping force.
  • the bracing of the measuring device In order to remove the measuring device from the bore in the event of a replacement that becomes necessary or to move the measuring device within the bore from one angular position to another, the bracing of the measuring device must be easily releasable.
  • the possibility of being able to move the measuring device is desirable if the direction of the force effect in the machine part is not known beforehand or is only known inaccurately and the converter is to be set to the maximum output signal by multiple pre-fixing in various rotational angle positions before the measuring device is finally fixed .
  • self-locking tensioning the release of the same is only possible in the known designs by an impact effect on the inner sleeve, and also only when the end of the inner sleeve that receives the impact is accessible.
  • the invention aims to create a measuring device of the type mentioned, which does not have the disadvantages described, is simpler and more compact and can be produced more cost-effectively, enables the use of commercially available, standard-produced quartz crystal transducers in miniature design and in any desired axial and rotational angle position within a hole can be mounted.
  • the measuring device is characterized in that the device has an essentially cylindrical sleeve as the outer boundary, which is provided with an inner cone at one end, that the transducer is connected to a screw spindle arranged coaxially in the sleeve, and one with the screw spindle for the axial movement of the engaging screw device is held axially non-displaceably in the interior of the sleeve and that the transducer has diametrically opposed force introduction elements which can be brought directly into engagement with the inner cone of the sleeve for its bracing expansion.
  • a device for holding the device in a specific axial and / or rotational angle position relative to the bore and a device for actuating the screwing device are provided, which devices do not substantially exceed the radial dimension of the sleeve.
  • each force introduction element comprises a pressure body which projects essentially radially from the transducer and has an essentially spherical cap-shaped end face which engages with the inner cone of the sleeve.
  • the electromechanical transducer intended for use in the measuring device according to the invention is preferably a piezoelectric transducer, in which the transducer elements, for example in the form of quartz crystal platelets, are arranged with them between the pressure bodies accommodating them in a hermetically sealed housing which has a tubular fastening attachment with an external thread through which the electrical connection line from the transducer elements is guided to the outside.
  • the pressure bodies forming part of the housing either have the shape of a Kugelkalo tte on the outside forming the force introduction surface, or they have plane-parallel force introduction surfaces, are placed on the spherical caps.
  • an electromechanical transducer of another type for example a piezoresistive transducer, can also be provided.
  • the expediently hollow screw spindle can be provided with an internal thread at the end on the transducer side, with which the screw spindle can be screwed tightly to the fastening attachment of the transducer housing.
  • the sleeve can be made from drawn tube.
  • the necessary operations are essentially limited to the rubbing out of the inner cone and the preparation of the bearing points for the axial fixation of the movement nut on both sides, which is provided for the axial displacement of the screw spindle.
  • the sleeve can additionally be provided with longitudinal slots which extend at least over the length of the inner cone.
  • snap rings inserted into the grooves can be provided on the sleeve.
  • the sleeve can be relatively thin-walled under these circumstances, e.g. have a wall thickness of 1 mm, especially if the tightening of the inner cone is small, e.g. 1: 10.
  • the bearing point closer to the inner cone can also be formed by a shoulder provided in the sleeve.
  • the force is introduced into the electromechanical transducer via spherical caps, which interact directly with the inner cone of the sleeve.
  • spherical caps which interact directly with the inner cone of the sleeve.
  • the direct action of the inner cone of the sleeve on the spherical caps of the piezoelectric transducer means that the line of action of the force application does not exactly coincide with the geometrical axis of the transducer.
  • this form of force application which deviates from the ideal, has only an insignificant influence on the mode of operation of the transducer, provided the tightening of the inner cone is not excessively large. It has been shown that the bending moments to be expected with an inner cone with a tightening of at most 1: 5 do not impair the transducer properties. Any shear forces are normally absorbed by the converter housing and are not included in the measurement.
  • a transducer which has both transducer elements for detecting pressure forces and transducer elements for detecting thrust forces and in which, in contrast to the previously described transducer, the introduced thrust forces are transmitted to the relevant transducer elements.
  • Piezoelectric transducers of this type are known per se and therefore require no further explanation.
  • the proposed simple construction makes it possible to manufacture the measuring device in the desired miniature version with relatively little effort.
  • This measuring device does not require any means for anchoring it at the mouth of the bore intended for its use in a machine part. Rather, it is suitable for so-called deep hole assembly and can be fixed at any depth within the hole. Furthermore, it has means in the form of axially gela on both sides erten movement nut, which make it possible to easily loosen the cone connection after fixing the measuring device, so that the measuring device can be moved according to the respective requirements.
  • Means for holding the measuring device in a specific axial and rotational angle position within a bore and means for actuating the movement nut are provided for mounting the measuring device.
  • These means can e.g. consist in the fact that the movement nut has a coaxial cylindrical projection which projects beyond the outer axial bearing of the movement nut and which carries a radial pin to which an auxiliary tool for displacing the measuring device in the axial direction and for rotating the movement nut can be attached, and that on the outside At least one flat contact surface is provided at the end of the screw spindle, which enables the attachment of an auxiliary tool for fixing the angular position of the screw spindle and thus the transducer.
  • Suitable auxiliary tools are two coaxial tubes that can be moved and twisted into one another, that can be inserted into the bore and that have actuating handles at one end and molded parts at the other end, which can be brought into engagement with the relevant actuating elements on the measuring device.
  • the movement nut can be made of a material whose modulus of elasticity is lower than that of the electromechanical transducer, e.g. made of an aluminum alloy or plastic. This measure also leads to a damping of the natural resonances of the transducer.
  • the electrical line connected to the transducer ground is normally led out in an insulated manner and grounded on the device for evaluating the electrical transducer signals.
  • the transformer mass in be electrically insulated from the surrounding mass, in particular from the bore wall surrounding the measuring device in use.
  • a sleeve can be used for the measuring device which, at least on its outside, consists of electrically non-conductive material, that is to say, for example, is provided with a surface layer made of aluminum oxide.
  • Other possibilities for ground insulation arise on the basis of claim 15.
  • the measuring electronics and evaluation logic connected to the converter for example comprising amplifiers, analog-digital converters, programmable memories, can be partially or completely accommodated in the housing also containing the converter and / or the connecting pipe connected to it, and can thus be integrated into the measuring device.
  • This integration offers advantages especially in applications in which a compact design of the overall system comprising a mechanical and an electronic part and a low susceptibility to interference signals, e.g. electromagnetic type, are important. This is the case, for example, in a machine room.
  • the measuring device 1 which according to FIG. 1 is inserted into a cylindrical bore 2 in a mechanically stressed machine part 3 to be monitored, for example in a machine tool table, has an outer boundary of a thin-walled cylindrical sleeve 4, which at one end has an inner cone 5 is provided.
  • the electromechanical transducer 6 consists of a hermetically sealed housing 7 containing the transducer elements, for example quartz crystal platelets, to which a tubular fastening attachment 8 with an external thread 9 connects, and two diametrically opposed pressure bodies 10, each with a spherical cap 11 for the introduction of force.
  • the spherical caps 11 can be formed on the pressure bodies 10 or placed on them.
  • the radius of the spherical caps 11 is preferably the same size as the radius of the inner cone 5 of the sleeve 4 at the narrowest point.
  • the electrical connecting line 12 is led outward from the transducer elements through the cavity of the fastening projection 8.
  • Piezoelectric transducers of this type are commercially available as series products.
  • the housing 7 and / or the attachment 8 can, as already mentioned, contain the measuring electronics and evaluation logic partially or entirely.
  • a screw spindle 13 is arranged coaxially, which is screwed onto the external thread 9 of the fastening attachment 8 and is thus firmly connected to the transducer 6.
  • two plane-parallel engagement surfaces 14 are provided for attaching an auxiliary tool (not shown), for example in the form of a socket wrench, with which the screw spindle 13 can be held from the outside in a certain angle of rotation position.
  • a screwed motion nut 15 is provided, which is guided radially on the inside of the sleeve 4 and is axially supported on both sides.
  • two snap rings 16 inserted in annular grooves on the sleeve 4 serve as axial bearings and 17.
  • the movement nut 15 has a cylindrical projection 18 which projects beyond the outer axial bearing 17.
  • This extension 18 carries a radial pin 19 to which an auxiliary tool (not shown) for moving the measuring device in the axial direction and for rotating the movement nut can be attached.
  • This auxiliary tool can be a tube with a longitudinal slot, which has two optionally usable cross slots at the attachment point for gripping the pin 19, which extend from the longitudinal slot to both sides.
  • the screw spindle 13 which is secured against rotation with the auxiliary tool, can be axially displaced such that the transducer 6 is drawn into the sleeve 4 and braced in the region of the inner cone 5, the spherical caps 11 of the transducer 6 being connected to the inner cone 5 Collar 4 interact immediately.
  • the entire measuring device within the bore 2 is axially fixed by frictional engagement between the sleeve 4 and the bore wall, and the transducer 6 is preloaded.
  • the elasticity of its shape may under certain circumstances be sufficient to transmit the clamping force exerted on the inner cone 5 only at two diametrical locations without excessive force being exerted on the moving nut 15.
  • longitudinal slots 21 which extend at least over the length of the inner cone 5, in a manner known per se.
  • the width of the longitudinal slots 21 should be small in relation to the radius of the spherical caps 11 of the transducer 6, so that they do not form any catches for the spherical caps.
  • the second embodiment of the measuring device 23 according to FIG. 4 differs from the one described above in that, starting from a somewhat thick-walled sleeve 24, the axial bearing of the movement nut 15 closer to the inner cone 25 is formed by a shoulder 26 on the sleeve 24 and in that other means for setting the measuring device are provided.
  • the remaining parts of the measuring device essentially correspond to those according to FIGS. 1 to 3 and are provided with the same reference numerals.
  • the sleeve 24 has at its end facing away from the inner cone 25 a radial pin 27 to which an auxiliary tool can be attached, which can basically be of the same design as that for the detection of the pin 19 in the first embodiment according to FIGS. 1 to 3.
  • a reversal of the shapes of the auxiliary tool and adjusting means is also possible.
  • the sleeve 24 has a longitudinal slot 28 starting from the sleeve edge and two transverse slots 29 (shown in dash-dot lines) extending from the latter and extending to both sides, while the auxiliary tool has a radial pin for insertion into these slots.
  • the screw spindle 13 with the transducer 6 is secured against rotation relative to the sleeve 24 by a pin 30 which is inserted radially at the end of the screw spindle 13 on the converter side and is guided in a longitudinal slot 31 of the sleeve 24.
  • two plane-parallel engagement surfaces 20 are provided on a cylindrical extension 18 of the movement nut 15, which enable the attachment of an auxiliary tool for rotating the movement nut 15.
  • the auxiliary tool for rotating the movement nut 15 can be arranged within that for holding the measuring device. This facilitates the handling of the auxiliary tools, since with this solution the handles of the turning tool are outside of the those of the holding tool come to rest.
  • the means arranged on the measuring device for inserting the same into a bore are designed such that their radial expansion does not exceed the outer diameter of the sleeve.
  • the measuring device is therefore also suitable for deep hole mounting.
  • the auxiliary tool intended to hold the measuring device can be provided on its outside with a length scale.
  • the inner cone of the sleeve can also run in the opposite direction, i.e. have its narrowest point at the end of the sleeve and expand inwards.
  • the electromechanical transducer can be insulated from ground in various ways.
  • the sleeve can have a wear-resistant layer made of an electrically non-conductive material (e.g. aluminum oxide) at least on the outer wall.
  • an electrically non-conductive material e.g. aluminum oxide
  • the spherical caps are placed on the pressure bodies of the transducer and either consist of electrically non-conductive material or are connected to the pressure bodies by means of an electrically non-conductive adhesive, and that the movement nut, at least on the outside, consists of an electrically non-conductive Material exists.
  • the measuring device can also be used where it is a matter of absorbing tangential shear forces F S (FIG. 3) in addition to compressive forces F D and measuring them individually.
  • F S tangential shear forces
  • F D compressive forces
  • an electromechanical converter is to be provided for this purpose, which is set up for the separate detection of pressure and thrust forces.
  • a sleeve with longitudinal slots in the cone area must also be used.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)
  • Measuring Fluid Pressure (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
  • Steering Control In Accordance With Driving Conditions (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
  • Testing Of Balance (AREA)

Abstract

A force measuring device includes a transducer mounted on a screw spindle, having force introducing elements interacting directly with the inside taper of a cylindrical sleeve to brace the device in a hold and preload the transducer. The screw spindle is displaced by a moving nut which is guided radially in the sleeve and supported axially at both sides. For bracing the device in a hole, mechanisms are provided for holding the force measuring device in a defined axial position and angle of rotation and for actuating the moving nut. These mechanisms do not extend beyond the outside diameter of the sleeve.

Description

Die Erfindung betrifft eine Messvorrichtung mit einem elektromechanischen Wandler zur Messung der Kraftwirkungen in einem mechanisch belasteten Maschinenteil oder dgl., welche in einer Bohrung des Maschinenteils einsetzbar und darin unter gleichzeitigem Vorspannen des Wandlers kraftschlüssig verspannbar ist.The invention relates to a measuring device with an electromechanical transducer for measuring the force effects in a mechanically loaded machine part or the like. Which can be used in a bore in the machine part and can be non-positively clamped therein while simultaneously pretensioning the transducer.

Messvorrichtungen mit elektromechanischen Wandlern sind an sich bekannt (US-A- 4 412 456, DE-A- 34 07 620). Sie dienen vornehmlich zur Erfassung von Teilkräften bzw. Materialdehnungen in einem mechanisch belasteten Maschinenteil und liefern ein elektrisches Signal, welches ein Mass für die auf das Maschinenteil einwirkende Kraft darstellt. Piezoelektrische Wandler, insbesondere solche mit Quarzkristallelementen, finden dank ihrer hohen Empfindlichkeit bevorzugt Anwendung in derartigen Messvorrichtungen, da diese auch an Stellen eingesetzt werden können, wo nur verhältnismässig geringe Teilkräfte auftreten.Measuring devices with electromechanical transducers are known per se (US-A-4 412 456, DE-A-34 07 620). They are primarily used to record partial forces or material strains in a mechanically loaded machine part and provide an electrical signal that represents a measure of the force acting on the machine part. Thanks to their high sensitivity, piezoelectric transducers, in particular those with quartz crystal elements, are preferably used in such measuring devices, since they can also be used in places where only relatively small partial forces occur.

In der DE- A-34 07 620 ist eine Messvorrichtung mit einem piezoelektrischen Wandler beschrieben, die in der oben beschriebenen Weise in die Bohrung eines Maschinenteils eingesetzt und darin verspannt werden kann. Sie besitzt zwei koaxial angeordnete, teilweise längsgeschlitzte, in Axialrichtung relativ zueinander bewegbare Hülsen, die nach Art eines Spreizdübels zusammenwirken. Dazu ist an dem in der Bohrung tiefer liegenden Ende der inneren Hülse eine Konusfläche vorgesehen, die gegen die andere Hülse drückt. Die Innenhülse weist im Bereich der Konusfläche zwei planparallele Flächen auf, zwischen denen der piezoelektrische Wandler eingespannt ist. Beim Ineinanderschieben der beiden Hülsen werden die durch Längsschlitze geteilten Schenkel der Aussenhülse infolge der Keilwirkung an der Konusfläche gespreizt, wodurch die Messvorrichtung an der Bohrungswandung kraftschlüssig festgelegt wird. Zugleich wird der piezoelektrische Wandler zwischen den Planflächen an den durch Längsschlitze geteilten Schenkeln der Innenhülse vorgespannt. Ferner weist die Aussenhülse einen Kopf auf, der entweder an der Aussenseite des Maschinenteils auzuliegen bestimmt ist oder in eine Erweiterung der Bohrungsmündung zu liegen kommt und als Gegenlager für eine Spannmutter dient.DE-A-34 07 620 describes a measuring device with a piezoelectric transducer which can be inserted into the bore of a machine part in the manner described above and clamped therein. It has two coaxially arranged, partially longitudinally slotted sleeves which are movable in the axial direction relative to one another and which are in the manner of a Interact with expansion plugs. For this purpose, a conical surface is provided at the end of the inner sleeve that is deeper in the bore and presses against the other sleeve. The inner sleeve has two plane-parallel surfaces in the area of the cone surface, between which the piezoelectric transducer is clamped. When the two sleeves are pushed into one another, the legs of the outer sleeve divided by longitudinal slots are spread as a result of the wedge effect on the conical surface, as a result of which the measuring device is non-positively fixed to the bore wall. At the same time, the piezoelectric transducer is prestressed between the flat surfaces on the legs of the inner sleeve divided by longitudinal slots. Furthermore, the outer sleeve has a head, which is either intended to be placed on the outside of the machine part or comes to lie in an extension of the bore opening and serves as a counter bearing for a clamping nut.

Die Konstruktion dieser Messvorrichtung ist verhältnismässig kompliziert und aufwendig in bezug auf Material und Herstellung. Z.B. erfordert die Fassung des piezoelektrischen Wandlers planparallele Flächen an der Innenseite der Innenhülse. Für eine einwandfreie Krafteinleitung unter Vermeidung eines Kraftnebenschlusses und von Biegemomenten müssen die die Planflächen aufweisenden Schenkel der Innenhülse sehr elastisch und beispielsweise verhältnismässig lang sein, wobei die Länge der Längsschlitze die Gesamtlänge der Messvorrichtung mitbestimmt. Die Aussenhülse ist wegen des vorgesehenen Kopfes aus massivem Material herauszuarbeiten.The construction of this measuring device is relatively complicated and expensive in terms of material and manufacture. E.g. requires the mounting of the piezoelectric transducer plane-parallel surfaces on the inside of the inner sleeve. For a perfect introduction of force, avoiding a force bypass and bending moments, the legs of the inner sleeve that have the flat surfaces must be very elastic and, for example, relatively long, the length of the longitudinal slots also determining the overall length of the measuring device. The outer sleeve is to be made out of solid material because of the intended head.

Die Anordnung des piezoelektrischen Wandlers zwischen planparallelen Flächen der Innenhülse ist insofern nachteilig, als eine definierte Lage der Wirkungslinie der in den Wandler einzuleitenden Kraft kaum zu erreichen ist. Falls diese Wirkungslinie exzentrisch bzw. schiefwinklig zur Wandlerachse verläuft, treten Biegemomente auf, welche die Arbeitsweise des Wandlers unter Umständen erheb lich beeinträchtigen können. Bei den Ausführungsformen nach der DE-A- 34 07 620 hängt die relative Lage der Wirkungslinie der Krafteinleitung von verschiedenen Masstoleranzen ab. Einerseits hat der Wandler keine definierte Lage in Richtung der Längsachse der Messvorrichtung, und andererseits ist die relative Lage der beiden Hülsen in axialer Richtung nicht definiert, was bei der Konstruktion mit an der Innenhülse vorgesehener Konusfläche zur Folge hat, dass die axiale Lage des auf die Konusfläche drückenden, die Krafteinleitung auf die Innenhülse bewirkenden Randes der Aussenhülse je nach den Abweichungen vom Sollwert d er massgeblichen Abmessungen der beiden Hülsen im Konusbereich variieren kann.The arrangement of the piezoelectric transducer between plane-parallel surfaces of the inner sleeve is disadvantageous in that a defined position of the line of action of the force to be introduced into the transducer can hardly be achieved. If this line of action is eccentric or at an oblique angle to the transducer axis, bending moments occur which may increase the mode of operation of the transducer Lich impair. In the embodiments according to DE-A-34 07 620, the relative position of the line of action of the force application depends on different dimensional tolerances. On the one hand, the transducer has no defined position in the direction of the longitudinal axis of the measuring device, and on the other hand, the relative position of the two sleeves in the axial direction is not defined, which has the consequence in the design with the conical surface provided on the inner sleeve that the axial position of the Pressing the conical surface, the force on the inner sleeve causing the force of the outer sleeve can vary depending on the deviations from the target value of the relevant dimensions of the two sleeves in the cone area.

In der DE-A- 34 07 620 ist auch eine Ausführungsform beschrieben, bei der als Gewindeverbindung eine Madenschraube vorgesehen ist, welche in ein Innengewinde der Aussenhülse eingeschraubt ist und zur Erzeugung der axialen Spannkraft auf die Innenhülse drückt. Bei dieser Konstruktion ist die Drehwinkellage des Wandlers unbestimmt und von aussen nicht kontrollierbar.DE-A-34 07 620 also describes an embodiment in which a grub screw is provided as the threaded connection, which is screwed into an internal thread of the outer sleeve and presses on the inner sleeve to generate the axial clamping force. With this construction, the angular position of the transducer is indefinite and cannot be controlled from the outside.

Zur Entfernung der Messvorrichtung aus der Bohrung im Falle eines notwenig werdenden Ersatzes oder zum Versetzen der Messvorrichtung innerhalb der Bohrung von einer Drehwinkellage in eine andere, muss die Verspannung der Messvorrichtung leicht lösbar sein. Unter anderem ist die Möglichkeit, die Messvorrichtung versetzen zu können, dann erwünscht, wenn die Richtung der Kraftwirkung im Maschinenteil vorab nicht oder nur ungenau bekannt ist und der Wandler vor der endgültigen Fixierung der Messvorrichtung durch mehrfaches Vorfixieren in verschiedenen Drehwinkellagen auf maximales Ausgangssignal eingestellt werden soll. Bei selbsthemmender Verspannung ist das Lösen derselben bei den bekannten Ausführungen nur möglich durch eine Schlagwirkung auf die Innenhülse, und auch nur dann, wenn das den Schlag aufnehmende Ende der Innenhülse zugänglich ist. Dieses Verfahren kann allerdings den Wandler gefährden. Für eine nicht selbsthemmende Verspannung ist demgegenüber ein kleineres Uebersetzungsverhältnis in bezug auf die Kraftumsetzung an der Konusfläche in Kauf zu nehmen, so dass an der Gewindeverbindung zwischen den beiden Hülsen höhere Spannkräfte aufzubringen sind.In order to remove the measuring device from the bore in the event of a replacement that becomes necessary or to move the measuring device within the bore from one angular position to another, the bracing of the measuring device must be easily releasable. Among other things, the possibility of being able to move the measuring device is desirable if the direction of the force effect in the machine part is not known beforehand or is only known inaccurately and the converter is to be set to the maximum output signal by multiple pre-fixing in various rotational angle positions before the measuring device is finally fixed . In the case of self-locking tensioning, the release of the same is only possible in the known designs by an impact effect on the inner sleeve, and also only when the end of the inner sleeve that receives the impact is accessible. However, this procedure can endanger the converter. In contrast, for a non-self-locking bracing, there is a smaller transmission ratio in relation to the force conversion to be accepted on the conical surface, so that higher clamping forces have to be applied to the threaded connection between the two sleeves.

Die Erfindung bezweckt demgegenüber die Schaffung einer Messvorrichtung der eingangs genannten Art, welche die beschriebenen Nachteile nicht aufweist, einfacher und kompakter aufgebaut und kostengünstiger herstellbar ist, den Einsatz handelsüblicher, serienmässig hergestellter Quarzkristall-Wandler in Miniaturausführung ermöglicht und in jeder gewünschten Axial- und Drehwinkellage innerhalb einer Bohrung montiert werden kann.In contrast, the invention aims to create a measuring device of the type mentioned, which does not have the disadvantages described, is simpler and more compact and can be produced more cost-effectively, enables the use of commercially available, standard-produced quartz crystal transducers in miniature design and in any desired axial and rotational angle position within a hole can be mounted.

Die erfindungsgemäße Messvorrichtung zeichnet sich dadurch aus, dass die Vorrichtung als äussere Begrenzung eine im wesentlichen zylindrische Hülse aufweist, die an einem Ende mit einem Innenkonus versehen ist, dass der Wandler mit einer in der Hülse koaxial angeordneten Schraubspindel verbunden ist, dass eine mit der Schraubspindel zu deren axialen Bewegung in Eingriff stehende Schraubeinrichtung im Innern der Hülse axial unverschieblich drehbar gehalten ist, und dass der Wandler diametral gegenüberliegende Krafteinleitungselemente aufweist, welche mit dem Innenkonus der Hülse zu deren verspannenden Spreizung unmittelbar in Eingriff bringbar sind.The measuring device according to the invention is characterized in that the device has an essentially cylindrical sleeve as the outer boundary, which is provided with an inner cone at one end, that the transducer is connected to a screw spindle arranged coaxially in the sleeve, and one with the screw spindle for the axial movement of the engaging screw device is held axially non-displaceably in the interior of the sleeve and that the transducer has diametrically opposed force introduction elements which can be brought directly into engagement with the inner cone of the sleeve for its bracing expansion.

Gemäss einer bevorzugten Weiterbildung der Erfindung sind eine Einrichtung zum Halten der Vorrichtung in einer bestimmten Axial- und/oder Drehwinkellage gegenüber der Bohrung und eine Einrichtung zum Betätigen der Schraubeinrichtung vorgesehen, welche Einrichtungen die radiale Abmessung der Hülse im wesentlichen nicht überschreiten.According to a preferred development of the invention, a device for holding the device in a specific axial and / or rotational angle position relative to the bore and a device for actuating the screwing device are provided, which devices do not substantially exceed the radial dimension of the sleeve.

Gemäss einer anderen bevorzugten Weiterbildung der Erfindung umfasst jedes Krafteinleitungselement einen vom Wandler im wesentlichen radial abstehenden Druckkörper mit einer im wesentlichen kugelkalottenförmigen, mit dem Innenkonus der Hülse in Eingriff stehenden Stirnfläche.According to another preferred development of the invention, each force introduction element comprises a pressure body which projects essentially radially from the transducer and has an essentially spherical cap-shaped end face which engages with the inner cone of the sleeve.

Der für den Einsatz in der erfindungsgemässen Messvorrichtung vorgesehene elektromechanische Wandler ist vorzugsweise ein piezoelektrischer Wandler, bei dem die Wandlerelemente z.B. in Form vom Quarzkristallplättchen mit diese zwischen sich aufnehmenden Druckkörpern in einem hermetisch geschlossenen Gehäuse angeordnet sind, das einen rohrförmigen Befestigungsansatz mit Aussengewinde aufweist, durch den die elektrische Verbindungsleitung von den Wandlerelementen nach aussen geführt ist. Die einen Teil des Gehäuses bildenden Druckkörper haben an der die Krafteinleitungsfläche bildenden Aussenseite entweder die Form einer Kugelkalo tte, oder sie besitzen planparallele Krafteinleitungsflächen, auf die Kugelkalotten aufgesetzt werden. Als Variante kann auch ein elektromechanischer Wandler anderer Art, z.B. ein piezoresistiver Wandler vorgesehen sein.The electromechanical transducer intended for use in the measuring device according to the invention is preferably a piezoelectric transducer, in which the transducer elements, for example in the form of quartz crystal platelets, are arranged with them between the pressure bodies accommodating them in a hermetically sealed housing which has a tubular fastening attachment with an external thread through which the electrical connection line from the transducer elements is guided to the outside. The pressure bodies forming part of the housing either have the shape of a Kugelkalo tte on the outside forming the force introduction surface, or they have plane-parallel force introduction surfaces, are placed on the spherical caps. As a variant, an electromechanical transducer of another type, for example a piezoresistive transducer, can also be provided.

Für die Befestigung des Wandlers an der Schraubenspindel kann die zweckmässigerweise hohl ausgeführte Schraubenspindel am wandlerseitigen Ende mit einem Innengewinde versehen sein, mit dem die Schraubspindel am Befestigungsansatz des Wandlergehäuses festgeschraubt werden kann.For the fastening of the transducer to the screw spindle, the expediently hollow screw spindle can be provided with an internal thread at the end on the transducer side, with which the screw spindle can be screwed tightly to the fastening attachment of the transducer housing.

Die Hülse kann aus gezogenem Rohr hergestellt werden. Die erforderlichen Arbeitsgänge beschränken sich im wesentlichen auf das Ausreiben des Innenkonus und die Vorbereitung der Lagerstellen für die beidseitige axiale Fixierung der Bewegungsmutter, welche für die axiale Verschiebung der Schraubspindel vorgesehen ist. Im Bedarfsfall kann die Hülse zusätzlich mit wenigstens über die Länge des Innenkonus sich erstreckenden Längsschlitzen versehen sein. Zur axialen beidseitigen Lagerung der Bewegungsmutter können an der Hülse in Ringnuten eingesetzte Sprengringe vorgesehen sein. Die Hülse kann unter diesen Umständen verhältnismässig dünnwandig sein, z.B. eine Wandstärke von 1 mm aufweisen, insbesondere wenn der Anzug des Innenkonus gering ist, z.B. 1 : 10. Bei grösserem Anzug des Innenkonus und entsprechend grösserer Wandstärke der Hülse kann die dem Innenkonus näher liegende Lagerstelle auch durch eine in der Hülse vorgesehene Schulter gebildet sein.The sleeve can be made from drawn tube. The necessary operations are essentially limited to the rubbing out of the inner cone and the preparation of the bearing points for the axial fixation of the movement nut on both sides, which is provided for the axial displacement of the screw spindle. If necessary, the sleeve can additionally be provided with longitudinal slots which extend at least over the length of the inner cone. For the axial two-sided mounting of the moving nut, snap rings inserted into the grooves can be provided on the sleeve. The sleeve can be relatively thin-walled under these circumstances, e.g. have a wall thickness of 1 mm, especially if the tightening of the inner cone is small, e.g. 1: 10. With a larger tightening of the inner cone and a correspondingly greater wall thickness of the sleeve, the bearing point closer to the inner cone can also be formed by a shoulder provided in the sleeve.

Die Krafteinleitung in den elektromechanischen Wandler erfolgt über Kugelkalotten, welche mit dem Innenkonus der Hülse unmittelbar zusammenwirken. Einerseits wird dadurch eine eindeutige, von Masstoleranzen weitgehend unabhängige Krafteinleitung erreicht, und andererseits ist bei dieser Konstruktion der auf ein Mindestmass zu beschränkende Durchmesser der Messvorrichtung im wesentlichen nur durch die radialen Abmessungen des Wandlers bestimmt.The force is introduced into the electromechanical transducer via spherical caps, which interact directly with the inner cone of the sleeve. On the one hand, this leads to a clear application of force that is largely independent of dimensional tolerances, and on the other hand, in this construction, the diameter of the measuring device to be restricted to a minimum is essentially only determined by the radial dimensions of the transducer.

Die unmittelbare Einwirkung des Innenkonus der Hülse auf die Kugelkalotten des piezoelektrischen Wandlers bringt es mit sich, dass die Wirkungslinie der Krafteinleitung nicht genau mit der geometrischen Achse des Wandlers zusammenfällt. Diese von der idealen abweichende Form der Krafteinleitung hat jedoch auf die Wirkungsweise des Wandlers einen nur unbedeutenden Einfluss, sofern der Anzug des Innenkonus nicht übermässig gross ist. Es hat sich gezeigt, dass die zu erwartenden Biegemomente bei einem Innenkonus mit einem Anzug von höchstens 1 : 5 die Wandlereigenschaften nicht beeinträchtigen. Allfällige Schubkräfte werden normalerweise vom Wandlergehäuse aufgenommen und gehen nicht in die Messung ein.The direct action of the inner cone of the sleeve on the spherical caps of the piezoelectric transducer means that the line of action of the force application does not exactly coincide with the geometrical axis of the transducer. However, this form of force application, which deviates from the ideal, has only an insignificant influence on the mode of operation of the transducer, provided the tightening of the inner cone is not excessively large. It has been shown that the bending moments to be expected with an inner cone with a tightening of at most 1: 5 do not impair the transducer properties. Any shear forces are normally absorbed by the converter housing and are not included in the measurement.

Andererseits besteht die Möglichkeit, mit ein und derselben Messvorrichtung sowohl Druckkräfte als auch tangential gerichtete Schubkräfte separat zu erfassen. Dazu ist ein Wandler einzusetzen, der sowohl Wandlerelemente zur Erfassung von Druckkräften als auch Wandlerelemente zur Erfassung von Schubkräften aufweist und bei dem im Gegensatz zu dem vorher beschriebenen Wandler die eingeleiteten Schubkräfte auf die betreffenden Wandlerelemente übertragen werden. Piezoelektrische Wandler dieser Art sind an sich bekannt und bedürfen daher keiner weiteren Erläuterung.On the other hand, it is possible to separately measure both compressive forces and tangentially directed thrust forces with one and the same measuring device. For this purpose, a transducer is to be used which has both transducer elements for detecting pressure forces and transducer elements for detecting thrust forces and in which, in contrast to the previously described transducer, the introduced thrust forces are transmitted to the relevant transducer elements. Piezoelectric transducers of this type are known per se and therefore require no further explanation.

Die vorgeschlagene einfache Konstruktion erlaubt es, die Messvorrichtung mit verhältnismässig geringem Aufwand in der gewünschten Miniaturausführung herzustellen. Diese Messvorrichtung benötigt keine Mittel zu ihrer Verankerung an der Mündung der zu ihrem Einsatz vorgesehenen Bohrung in einem Maschinenteil. Sie ist vielmehr geeignet für eine sogenannte Tieflochmontage und kann in jeder beliebigen Tiefenlage innerhalb der Bohrung fixiert werden. Ferner verfügt sie über Mittel in Form der beidseitig axial gela gerten Bewegungsmutter, die es ermöglichen, nach einer Fixierung der Messvorrichtung die Konusverbindung leicht wieder zu lösen, so dass die Messvorrichtung den jeweiligen Erfordernissen entsprechend versetzt werden kann.The proposed simple construction makes it possible to manufacture the measuring device in the desired miniature version with relatively little effort. This measuring device does not require any means for anchoring it at the mouth of the bore intended for its use in a machine part. Rather, it is suitable for so-called deep hole assembly and can be fixed at any depth within the hole. Furthermore, it has means in the form of axially gela on both sides erten movement nut, which make it possible to easily loosen the cone connection after fixing the measuring device, so that the measuring device can be moved according to the respective requirements.

Für die Montage der Messvorrichtung sind Mittel zum Halten derselben in einer bestimmten Axial- und Drehwinkellage innerhalb einer Bohrung und Mittel zum Betätigen der Bewegungsmutter vorhanden. Diese Mittel können z.B. darin bestehen, dass die Bewegungsmutter einen koaxial zylindrischen Ansatz aufweist, der über das äussere Axiallager der Bewegungsmutter hinausragt und der einen radialen Zapfen trägt, an den ein Hilfswerkzeug zum Verschieben der Messvorrichtung in axialer Richtung und zum Verdrehen der Bewegungsmutter ansetzbar ist, und dass am äusseren Ende der Schraubspindel wenigstens eine plane Angriffsfläche vorgesehen ist, die das Ansetzen eines Hilfswerkzeuges zum Fixieren der Drehwinkellage der Schraubspindel und damit des Wandlers ermöglicht. Als Hilfswerkzeuge eignen sich zwei koaxiale, ineinander verschieb- und verdrehbare Rohre, die in die Bohrung einführbar sind und die am einen Ende Betätigungsgriffe und am anderen Ende Formteile aufweisen, die mit den betreffenden Stellelementen an der Messvorrichtung zum Eingriff gebracht werden können.Means for holding the measuring device in a specific axial and rotational angle position within a bore and means for actuating the movement nut are provided for mounting the measuring device. These means can e.g. consist in the fact that the movement nut has a coaxial cylindrical projection which projects beyond the outer axial bearing of the movement nut and which carries a radial pin to which an auxiliary tool for displacing the measuring device in the axial direction and for rotating the movement nut can be attached, and that on the outside At least one flat contact surface is provided at the end of the screw spindle, which enables the attachment of an auxiliary tool for fixing the angular position of the screw spindle and thus the transducer. Suitable auxiliary tools are two coaxial tubes that can be moved and twisted into one another, that can be inserted into the bore and that have actuating handles at one end and molded parts at the other end, which can be brought into engagement with the relevant actuating elements on the measuring device.

Um die Wirkung des über die Bewegungsmutter verlaufenden Kraftnebenschlusses zu vermindern, kann die Bewegungsmutter aus einem Material bestehen, dessen Elastizitätsmodul geringer ist als der des elektromechanischen Wandlers, z.B. aus einer Aluminiumlegierung oder aus Kunststoff. Diese Massnahme führt auch zu einer Dämpfung der Eigenresonanzen des Wandlers.In order to reduce the effect of the force shunt running over the movement nut, the movement nut can be made of a material whose modulus of elasticity is lower than that of the electromechanical transducer, e.g. made of an aluminum alloy or plastic. This measure also leads to a damping of the natural resonances of the transducer.

Bei den handelsüblichen piezoelektrischen Wandlern ist normalerweise die mit der Wandlermasse verbundene elektrische Leitung isoliert herausgeführt und jeweils am Gerät zur Auswertung der elektrischen Wandlersignale geerdet. Damit den Messvorgang störende Erdungsschlaufen vermieden werden, muss die Wandlermasse in bezug auf die Umgebungsmasse, insbesondere gegenüber der die Messvorrichtung im Einsatz umgebenden Bohrungswandung elektrisch isoliert sein. Im einfachsten Fall kann man dazu für die Messvorrichtung eine Hülse verwenden, die wenigstens an ihrer Aussenseite aus elektrisch nicht leitendem Material besteht, also beispielsweise mit einer Oberflächenschicht aus Aluminiumoxid versehen ist. Andere Möglichkeiten zur Masseisolation ergeben sich auf der Basis des Anspruches 15.In the case of commercially available piezoelectric transducers, the electrical line connected to the transducer ground is normally led out in an insulated manner and grounded on the device for evaluating the electrical transducer signals. In order to avoid ground loops that interfere with the measuring process, the transformer mass in be electrically insulated from the surrounding mass, in particular from the bore wall surrounding the measuring device in use. In the simplest case, a sleeve can be used for the measuring device which, at least on its outside, consists of electrically non-conductive material, that is to say, for example, is provided with a surface layer made of aluminum oxide. Other possibilities for ground insulation arise on the basis of claim 15.

Die an den Wandler anschliessende Messelektronik und Auswertungslogik, beispielsweise umfassend Verstärker, Analog-Digital-Wandler, programmierbare Speicher, können teilweise oder ganz in das auch den Wandler enthaltende Gehäuse und/oder das daran anschliessende Ansatzrohr untergebracht und dadurch in die Messvorrichtung integriert werden. Diese Integration bietet Vorteile speziell bei Anwendungen, bei denen eine kompakte Bauweise des einen mechanischen und einen elektronischen Teil umfassenden Gesamtsystems und eine geringe Anfälligkeit für Störsignale, z.B. elektromagnetischer Art, wichtig sind. Dies ist der Fall beispielsweise in einem Maschinenraum.The measuring electronics and evaluation logic connected to the converter, for example comprising amplifiers, analog-digital converters, programmable memories, can be partially or completely accommodated in the housing also containing the converter and / or the connecting pipe connected to it, and can thus be integrated into the measuring device. This integration offers advantages especially in applications in which a compact design of the overall system comprising a mechanical and an electronic part and a low susceptibility to interference signals, e.g. electromagnetic type, are important. This is the case, for example, in a machine room.

In der Zeichung sind Ausführungsbeispiele der Erfindung dargestellt, und zwar zeigen:

  • Fig. 1 eine erste Ausführungsform der in eine Bohrung eines Maschinenteils eingesetzten Messvorrichtung, zur Hälfte in Ansicht und zur Hälfte im Längsschnitt;
  • Fig. 2 eine Stirnansicht der Messvorrichtung nach Fig. 1 in Richtung des Pfeiles A in Fig. 1;
  • Fig. 3 eine Stirnansicht der Messvorrichtung nach Fig. 1 in Richtung des Pfeiles B in Fig. 1; und
  • Fig. 4 eine zweite Ausführungsform der Messvorrichtung, zur Hälfte in Ansicht und zur Hälfte im Längsschnitt.
Exemplary embodiments of the invention are shown in the drawing, namely:
  • Figure 1 shows a first embodiment of the measuring device used in a bore of a machine part, half in view and half in longitudinal section.
  • FIG. 2 shows an end view of the measuring device according to FIG. 1 in the direction of arrow A in FIG. 1;
  • FIG. 3 shows an end view of the measuring device according to FIG. 1 in the direction of arrow B in FIG. 1; and
  • Fig. 4 shows a second embodiment of the measuring device, half in view and half in longitudinal section.

Die Messvorrichtung 1, welche nach Fig. 1 in eine zylindrische Bohrung 2 in einem zu überwachenden, mechanisch belasteten Maschinenteil 3, z.B. in einem Werkzeugmaschinentisch eingesetzt ist, hat als äussere Begrenzung eine dünnwandige zylindrische Hülse 4, welche an ihrem einen Ende mit einem Innenkonus 5 versehen ist. Der elektromechanische Wandler 6 besteht aus einem die Wandlerelemente, z.B. Quarzkristallplättchen, enthaltenden, hermetisch verschlossenen Gehäuse 7, an das sich ein rohrförmiger Befestigungsansatz 8 mit Aussengewinde 9 anschlie sst, und zwei einander diametral gegenüberliegenden Druckkörpern 10 mit je einer Kugelkalotte 11 zur Krafteinleitung. Die Kugelkalotten 11 können an den Druckkörpern 10 ausgebildet oder auf diese aufgesetzt sein. Der Radius der Kugelkalotten 11 ist vorzugsweise gleich gross wie der Radius des Innenkonus 5 der Hülse 4 an der engsten Stelle. Durch den Hohlraum des Befestigungsansatzes 8 ist die elektrische Verbindungsleitung 12 von den Wandlerelementen nach aussen geführt. Piezoelektrische Wandler dieser Art sind als Serienfabrikat handelsüblich. Das Gehäuse 7 und/oder der Ansatz 8 können überdies, wie bereits erwähnt, die Messelektronik und Auswertungslogik teilweise oder ganz enthalten. Innerhalb der Hülse 4 ist eine Schraubspindel 13 koaxial angeordnet, welche auf das Aussengewinde 9 des Befestigungsansatzes 8 aufgeschraubt und so mit dem Wandler 6 fest verbunden ist. Am freien Ende der Schraubspindel 13 sind zwei planparallele Angriffsflächen 14 zum Ansetzen eines Hilfswerkzeuges (nicht dargestellt), z.B. in Form eines Steckschlüssels, vorgesehen, womit die Schraubspindel 13 von aussen in einer bestimmten Drehwinkellage gehalten werden kann. Zur axialen Verschiebung der Schraubspindel 13 ist eine auf diese aufgeschraubte Bewegungsmutter 15 vorgesehen, die an der Innenseite der Hülse 4 radial geführt und axial beidseitig gelagert ist. Als Axiallager dienen bei der ersten Ausführungsform der Messvorrichtung zwei in Ringnuten an der Hülse 4 eingesetzte Sprengringe 16 und 17. Die Bewegungsmutter 15 weist einen zylindrischen Ansatz 18 auf, der über das äussere Axiallager 17 hinausragt. Dieser Ansatz 18 trägt einen radialen Zapfen 19, an den ein Hilfswerkzeug (nicht dargestellt) zum Verschieben der Messvorrichtung in axialer Richtung und zum Verdrehen der Bewegungsmutter ansetzbar ist. Dieses Hilfswerkzeug kann ein Rohr mit einem Längsschlitz sein, das an der Ansatzstelle zwei wahlweise benützbare Querschlitze zum Erfassen des Zapfens 19 aufweist, die sich vom Längsschlitz aus nach beiden Seiten erstrecken. Am Ansatz 18 der Bewegungsmutter 15 sind ausserdem zwei planparallele Angriffsflächen 20 für das Ansetzen eines anderen Hilfswerkzeuges vorgesehen, das verwendet werden kann, wenn der Ansatz 18 in der Betriebslage der Messvorrichtung aus der Bohrung 2 herausragt.The measuring device 1, which according to FIG. 1 is inserted into a cylindrical bore 2 in a mechanically stressed machine part 3 to be monitored, for example in a machine tool table, has an outer boundary of a thin-walled cylindrical sleeve 4, which at one end has an inner cone 5 is provided. The electromechanical transducer 6 consists of a hermetically sealed housing 7 containing the transducer elements, for example quartz crystal platelets, to which a tubular fastening attachment 8 with an external thread 9 connects, and two diametrically opposed pressure bodies 10, each with a spherical cap 11 for the introduction of force. The spherical caps 11 can be formed on the pressure bodies 10 or placed on them. The radius of the spherical caps 11 is preferably the same size as the radius of the inner cone 5 of the sleeve 4 at the narrowest point. The electrical connecting line 12 is led outward from the transducer elements through the cavity of the fastening projection 8. Piezoelectric transducers of this type are commercially available as series products. The housing 7 and / or the attachment 8 can, as already mentioned, contain the measuring electronics and evaluation logic partially or entirely. Inside the sleeve 4, a screw spindle 13 is arranged coaxially, which is screwed onto the external thread 9 of the fastening attachment 8 and is thus firmly connected to the transducer 6. At the free end of the screw spindle 13, two plane-parallel engagement surfaces 14 are provided for attaching an auxiliary tool (not shown), for example in the form of a socket wrench, with which the screw spindle 13 can be held from the outside in a certain angle of rotation position. For the axial displacement of the screw spindle 13, a screwed motion nut 15 is provided, which is guided radially on the inside of the sleeve 4 and is axially supported on both sides. In the first embodiment of the measuring device, two snap rings 16 inserted in annular grooves on the sleeve 4 serve as axial bearings and 17. The movement nut 15 has a cylindrical projection 18 which projects beyond the outer axial bearing 17. This extension 18 carries a radial pin 19 to which an auxiliary tool (not shown) for moving the measuring device in the axial direction and for rotating the movement nut can be attached. This auxiliary tool can be a tube with a longitudinal slot, which has two optionally usable cross slots at the attachment point for gripping the pin 19, which extend from the longitudinal slot to both sides. On the shoulder 18 of the moving nut 15 there are also two plane-parallel engagement surfaces 20 for the attachment of another auxiliary tool, which can be used when the shoulder 18 protrudes from the bore 2 in the operating position of the measuring device.

Durch Verdrehen der Bewegungsmutter 15 lässt sich die mit dem Hilfswerkzeug gegen Verdrehung gesicherte Schraubspindel 13 axial so verschieben, dass der Wandler 6 in die Hülse 4 hineingezogen und im Bereich des Innenkonus 5 verspannt wird, wobei die Kugelkalotten 11 des Wandlers 6 mit dem Innenkonus 5 der Hülse 4 unmittelbar zusammenwirken. Auf diese Weise wird sowohl die gesamte Messvorrichtung innerhalb der Bohrung 2 durch Reibungsschluss zwischen Hülse 4 und Bohrungswandung axial fixiert als auch der Wandler 6 vorgespannt. Bei einer dünnwandigen, z.B. aus gezogenem Stahlrohr hergestellten Hülse kann deren Formelastizität unter Umständen ausreichen, um die nur an zwei diametralen Stellen auf den Innenkonus 5 ausgeübte Spannkraft ohne übermässigen Kraftaufwand an der Bewegungsmutter 15 nach aussen zu übertragen. Immerhin besteht die Möglichkeit, die Elastizität der Hülse im Konusbereich durch Längsschlitze 21, welche sich wenigstens über die Länge des Innenkonus 5 erstrecken, in an sich bekannter Weise zu erhöhen. Dabei soll die Breite der Längsschlitze 21 klein sein im Verhältnis zum Radius der Kugelkalotten 11 des Wandlers 6, damit sie keine Rasten für die Kugelkalotten bilden. Durch Verdrehen der Bewegungsmutter 15 in umgekehrter Drehrichtung kann die Verspannung der Messvorrichtung ohne weiteres wieder gelöst werden.By turning the movement nut 15, the screw spindle 13, which is secured against rotation with the auxiliary tool, can be axially displaced such that the transducer 6 is drawn into the sleeve 4 and braced in the region of the inner cone 5, the spherical caps 11 of the transducer 6 being connected to the inner cone 5 Collar 4 interact immediately. In this way, the entire measuring device within the bore 2 is axially fixed by frictional engagement between the sleeve 4 and the bore wall, and the transducer 6 is preloaded. In the case of a thin-walled sleeve, for example made of drawn steel tube, the elasticity of its shape may under certain circumstances be sufficient to transmit the clamping force exerted on the inner cone 5 only at two diametrical locations without excessive force being exerted on the moving nut 15. After all, there is the possibility of increasing the elasticity of the sleeve in the cone area by means of longitudinal slots 21, which extend at least over the length of the inner cone 5, in a manner known per se. The width of the longitudinal slots 21 should be small in relation to the radius of the spherical caps 11 of the transducer 6, so that they do not form any catches for the spherical caps. By twisting the movement nut 15 in the opposite direction of rotation, the bracing of the measuring device can be released again without further notice.

Die zweite Ausführungsform der Messvorrichtung 23 gemäss Fig. 4 unterscheidet sich von der zuvor beschriebenen dadurch, dass, ausgehend von einer etwas dickwandigeren Hülse 24, das dem Innenkonus 25 näher liegende Axiallager der Bewegungsmutter 15 durch eine Schulter 26 an der Hülse 24 gebildet ist und dass andere Mittel zum Setzen der Messvorrichtung vorgesehen sind. Die übrigen Teile der Messvorrichtung stimmen im wesentlichen mit denjenigen nach den Fig. 1 bis 3 überein und sind mit gleichen Bezugszeichen versehen.The second embodiment of the measuring device 23 according to FIG. 4 differs from the one described above in that, starting from a somewhat thick-walled sleeve 24, the axial bearing of the movement nut 15 closer to the inner cone 25 is formed by a shoulder 26 on the sleeve 24 and in that other means for setting the measuring device are provided. The remaining parts of the measuring device essentially correspond to those according to FIGS. 1 to 3 and are provided with the same reference numerals.

Zum Verschieben der Messvorrichtung 23 in axialer Richtung und zum Fixieren der Drehwinkellage des Wandlers 6 weist die Hülse 24 an ihrem dem Innenkonus 25 abgewandten Ende einen radialen Zapfen 27 auf, an den ein Hilfswerkzeug ansetzbar ist, das grundsätzlich gleich ausgebildet sein kann wie dasjenige zum Erfassen des Zapfens 19 bei der ersten Ausführungsform nach den Fig. 1 bis 3. Als Alternative dazu ist auch eine Umkehr der Formen von Hilfswerkzeug und Stellmittel möglich. Die Hülse 24 hat in diesem Fall einen vom Hülsenrand ausgehenden Längsschlitz 28 und zwei von diesem ausgehende, nach beiden Seiten sich erstreckende Querschlitze 29 (strichpunktiert dargestellt), während das Hilfswerkzeug über einen radialen Zapfen zum Einführen in diese Schlitze verfügt. Die Schraubspindel 13 mit dem Wandler 6 ist gegen ein Verdrehen gegenüber der Hülse 24 durch einen Stift 30 gesichert, der am wandlerseitigen Ende der Schraubspindel 13 radial eingesetzt und in einem Längsschlitz 31 der Hülse 24 geführt ist. Analog zur ersten Ausführungsform sind an einem zylindrischen Ansatz 18 der Bewegungsmutter 15 zwei planparallele Angriffsflächen 20 vorgesehen, die das Ansetzen eines Hilfswerkzeuges zum Verdrehen der Bewegungsmutter 15 ermöglichen. Im Gegensatz zu den bei der ersten Ausführungsform erforderlichen Hilfswerkzeugen kann im vorliegenden Fall das Hilfswerkzeug zum Verdrehen der Bewegungsmutter 15 innerhalb desjenigen zum Halten der Messvorrichtung angeordnet sein. Dies erleichtert die Handhabung der Hilfswerkzeuge, da bei dieser Lösung die Handgriffe des Drehwerkzeuges ausserhalb der jenigen des Haltewerkzeuges zu liegen kommen.To move the measuring device 23 in the axial direction and to fix the angular position of the transducer 6, the sleeve 24 has at its end facing away from the inner cone 25 a radial pin 27 to which an auxiliary tool can be attached, which can basically be of the same design as that for the detection of the pin 19 in the first embodiment according to FIGS. 1 to 3. As an alternative to this, a reversal of the shapes of the auxiliary tool and adjusting means is also possible. In this case, the sleeve 24 has a longitudinal slot 28 starting from the sleeve edge and two transverse slots 29 (shown in dash-dot lines) extending from the latter and extending to both sides, while the auxiliary tool has a radial pin for insertion into these slots. The screw spindle 13 with the transducer 6 is secured against rotation relative to the sleeve 24 by a pin 30 which is inserted radially at the end of the screw spindle 13 on the converter side and is guided in a longitudinal slot 31 of the sleeve 24. Analogously to the first embodiment, two plane-parallel engagement surfaces 20 are provided on a cylindrical extension 18 of the movement nut 15, which enable the attachment of an auxiliary tool for rotating the movement nut 15. In contrast to the auxiliary tools required in the first embodiment, in the present case the auxiliary tool for rotating the movement nut 15 can be arranged within that for holding the measuring device. This facilitates the handling of the auxiliary tools, since with this solution the handles of the turning tool are outside of the those of the holding tool come to rest.

In beiden dargestellten Ausführungsformen sind die an der Messvorrichtung angeordneten Mittel zum Einsetzen derselben in eine Bohrung so ausgebildet, dass die radiale Ausdehnung derselben den Aussendurchmesser der Hülse nicht überschreitet. Damit eignet sich die Messvorrichtung auch für eine Tieflochmontage. Zur Bestimmung der Tiefenlage kann das zum Halten der Messvorrichtung bestimmte Hilfswerkzeug an seiner Aussenseite mit einer Längenmassskala versehen sein.In both of the illustrated embodiments, the means arranged on the measuring device for inserting the same into a bore are designed such that their radial expansion does not exceed the outer diameter of the sleeve. The measuring device is therefore also suitable for deep hole mounting. To determine the depth, the auxiliary tool intended to hold the measuring device can be provided on its outside with a length scale.

Als Alternative zu den dargestellten Ausführungsformen kann der Innenkonus der Hülse auch in umgekehrter Richtung verlaufen, d.h. seine engste Stelle an Ende der Hülse haben und sich nach innen erweitern.As an alternative to the illustrated embodiments, the inner cone of the sleeve can also run in the opposite direction, i.e. have its narrowest point at the end of the sleeve and expand inwards.

Wie eingangs erwähnt, kann die Isolierung des elektromechanischen Wandlers gegen Masse auf verschiedene Weise vorgenommen werden. Beispielsweise kann die Hülse wenigstens an der Aussenwandung eine verschleissfeste Schicht aus einem elektrisch nicht leitenden Material (z.B. Aluminiumoxid) aufweisen. Eine andere Möglichkeit besteht darin, dass die Kugelkalotten auf die Druckkörper des Wandlers aufgesetzt sind und entweder aus elektrisch nicht leitendem Material bestehen oder durch einen elektrisch nicht leitenden Kleber mit den Druckkörpern verbunden sind, und dass die Bewegungsmutter wenigstens an ihrer Aussenseite aus einem elektrisch nicht leitenden Material besteht.As mentioned at the beginning, the electromechanical transducer can be insulated from ground in various ways. For example, the sleeve can have a wear-resistant layer made of an electrically non-conductive material (e.g. aluminum oxide) at least on the outer wall. Another possibility is that the spherical caps are placed on the pressure bodies of the transducer and either consist of electrically non-conductive material or are connected to the pressure bodies by means of an electrically non-conductive adhesive, and that the movement nut, at least on the outside, consists of an electrically non-conductive Material exists.

Die Messvorrichtung kann auch dort zum Einsatz kommen, wo es darum geht, ausser Druckkräften F D tangentiale Schubkräfte F S (Fig. 3) aufzunehmen und diese einzeln zu messen. Wie bereits erwähnt, ist dazu ein elektromechanischer Wandler vorzusehen, der für die separate Erfassung von Druck- und Schubkräften eingerichtet ist. Ausserdem ist in diesem Fall eine Hülse mit Längsschlitzen im Konusbereich zu verwenden. The measuring device can also be used where it is a matter of absorbing tangential shear forces F S (FIG. 3) in addition to compressive forces F D and measuring them individually. As already mentioned, an electromechanical converter is to be provided for this purpose, which is set up for the separate detection of pressure and thrust forces. In this case, a sleeve with longitudinal slots in the cone area must also be used.

Claims (20)

1. Messvorrichtung mit einem elektromechanischen Wandler zur Messung der Kraftwirkungen in einem mechanisch belasteten Maschinenteil oder dgl., welche in einer Bohrung des Maschinenteils einsetzbar und darin unter gleichzeitigem Vorspannen des Wandlers kraftschlüssig verspannbar ist, dadurch gekennzeichnet, dass die Vorrichtung (1,23) als äussere Begrenzung eine im wese ntlichen zylindrische Hülse (4,24) aufweist, die an einem Ende mit einem Innenkonus (5,25) versehen ist, dass der Wandler (6) mit einer in der Hülse koaxial angeordneten Schraubspindel (13) verbunden ist, dass eine mit der Schraubspindel zu deren axialen Bewegung in Eingriff stehende Schraubeinrichtung (15) im Innern der Hülse axial unverschieblich drehbar gehalten ist, und dass der Wandler diametral gegenüberliegende Krafteinleitungselemente (10,11) aufweist, welche mit dem Innenkonus (5,25) der Hülse zu deren verspannenden Spreizung unmittelbar in Eingriff bringbar sind.1.Measuring device with an electromechanical transducer for measuring the force effects in a mechanically loaded machine part or the like, which can be used in a bore in the machine part and can be non-positively clamped therein while simultaneously pretensioning the transducer, characterized in that the device (1,23) as has an essentially cylindrical sleeve (4,24) which is provided at one end with an inner cone (5,25) that the transducer (6) is connected to a screw spindle (13) arranged coaxially in the sleeve, that a screw device (15), which is in engagement with the screw spindle for its axial movement, is held in the interior of the sleeve so that it cannot be rotated axially, and that the transducer has diametrically opposed force introduction elements (10, 11) which are connected to the inner cone (5, 25) Sleeve can be brought directly into engagement for the bracing spread. 2. Messvorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß eine Einrichtung (14,17) zum Halten der Vorrichtung in einer bestimmten Axial- und/oder Drehwinkellage gegenüber der Bohrung und eine Einrichtung (19,20) zum Betätigen der Schraubeinrichtung (15) vorgesehen sind, welche Einrichtungen die radiale Abmessung der Hülse (4,24) im wesentlichen nicht überschreiten.2. Measuring device according to claim 1, characterized in that a device (14, 17) for holding the device in a certain axial and / or rotational angle position relative to the bore and a device (19, 20) for actuating the screwing device (15) are provided are which devices do not substantially exceed the radial dimension of the sleeve (4,24). 3. Messvorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass jedes Krafteinleitungselement einen vom Wandler (6) im wesentlichen radial abstehenden Druckkörper (10) mit einer im wesentlichen kugelkalottenförmigen, mit dem Innenkonus (5,25) der Hülse (4,24) in Eingriff stehenden Stirnfläche (11) umfasst.3. Measuring device according to claim 1 or 2, characterized in that each force introduction element has a pressure body (10) projecting essentially radially from the transducer (6) and having an essentially spherical cap-shaped, with the inner cone (5.25) of the sleeve (4.24). engaging end face (11). 4. Messvorrichtung nach einem der vorhergehenden Ansprüche dadurch gekennzeichnet, dass sie einen piezoelektrischen Wandler aufweist.4. Measuring device according to one of the preceding claims, characterized in that it has a piezoelectric transducer. 5. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass sie einen elektromechanischen, insbesondere piezoelektrischen Wandler aufweist, der für die separate Erfassung sowohl von Druckkräften als auch von tangential gerichteten Schubkräften eingerichtet ist.5. Measuring device according to one of the preceding claims, characterized in that it has an electromechanical, in particular piezoelectric transducer, which is set up for the separate detection of both compressive forces and tangentially directed thrust forces. 6. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Hülse (4; 24) aus gezogenem Rohr hergestellt ist.6. Measuring device according to one of the preceding claims, characterized in that the sleeve (4; 24) is made of drawn tube. 7. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Steigung des Innenkonus (5; 25) höchstens 1 : 5 beträgt.7. Measuring device according to one of the preceding claims, characterized in that the slope of the inner cone (5; 25) is at most 1: 5. 8. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Hülse (4) mit wenigstens über die Länge des Innenkonus (5) sich erstreckenden Längsschlitzen (21) versehen ist.8. Measuring device according to one of the preceding claims, characterized in that the sleeve (4) with at least over the length of the inner cone (5) extending longitudinal slots (21) is provided. 9. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Hülse (4; 24) zur axialen Lagerung der Schraubeinrichtung (15) an wenigstens einer der beiden Lagerstellen eine Ringnut aufweist, in die ein Sprengring (17) eingesetzt ist.9. Measuring device according to one of the preceding claims, characterized in that the sleeve (4; 24) for the axial mounting of the screwing device (15) has at least one of the two bearing points, an annular groove into which a snap ring (17) is inserted. 10. Messvorrichtung nach Anspruch 9, dadurch gekennzeichnet, dass die andere Lagerstelle durch eine Schulter (26) an der Hülse (24) gebildet ist.10. Measuring device according to claim 9, characterized in that the other bearing point is formed by a shoulder (26) on the sleeve (24). 11. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Schraubeinrichtung (15) aus einem Material besteht, dessen Elastizitätsmodul geringer ist als der des Wandlers (6).11. Measuring device according to one of the preceding claims, characterized in that the screw device (15) consists of a material whose modulus of elasticity is lower than that of the transducer (6). 12. Messvorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass der Radius der Kugelkalotte (11) an den Druckkörpern (10) etwa gleich gross ist wie der halbe Durchmesser des Innenkonus (15; 25) der Hülse an der engsten Stelle.12. Measuring device according to one of the preceding claims, characterized in that the radius of the spherical cap (11) on the pressure bodies (10) is approximately the same size as half the diameter of the inner cone (15; 25) of the sleeve at the narrowest point. 13. Messvorrichtung nach Anspruch 8, dadurch gekennzeichnet, dass die Breite der Längsschlitze (21) in der Hülse klein ist im Verhältnis zum Radius der Kugelkalotten (11).13. Measuring device according to claim 8, characterized in that the width of the longitudinal slots (21) in the sleeve is small in relation to the radius of the spherical caps (11). 14. Messvorrichtung nach einem der vorhergehenden Ansprüche dadurch gekennzeichnet, dass der elektromechanische Wandler (6) ein hermetisch abgeschlossenes Gehäuse (7) aufweist.14. Measuring device according to one of the preceding claims, characterized in that the electromechanical transducer (6) has a hermetically sealed housing (7). 15. Messvorrichtung nach einem der vorhergehenden Ansprüche dadurch gekennzeichnet, dass sie Mittel zur elektrischen Isolierung des elektromechanischen Wandlers gegen Masse aufweist.15. Measuring device according to one of the preceding claims, characterized in that it has means for electrically isolating the electromechanical transducer from ground. 16. Messvorrichtung nach Anspruch 15, dadurch gekennzeichnet, dass die zylindrische Hülse (4; 24) wenigstens an ihrer Aussenwandung aus elektrisch nicht leitendem Material besteht.16. Measuring device according to claim 15, characterized in that the cylindrical sleeve (4; 24) consists of electrically non-conductive material at least on its outer wall. 17. Messvorrichtung nach Anspruch 15, dadurch gekennzeichnet, d ass die Kugelkalotten (11) auf die Druckkörper (10) des Wandlers (6) aufgesetzt sind und entweder aus elektrisch nicht leitendem Material bestehen oder durch einen elektrisch nicht leitenden Kleber mit den Druckkörpern verbunden sind, und dass die Schraubeinrichtung (15) wenigstens an ihrer Aussenseite aus einem elektrisch nicht leitenden Material besteht.17. Measuring device according to claim 15, characterized in that the spherical caps (11) are placed on the pressure body (10) of the transducer (6) and either made of electrically non-conductive material exist or are connected to the pressure bodies by an electrically non-conductive adhesive, and that the screw device (15) consists of an electrically non-conductive material at least on its outside. 18. Messvorrichtung nach einem der vorhergehenden Ansprüche dadurch gekennzeichnet, dass die Schraubeinrichtung (15) einen koaxial zylindrischen Ansatz (18) aufweist, der über das äussere Axiallager (17) der Schraubeinrichtung hinausragt und der einen radialen Zapfen (19) trägt, an den ein Hilfswerkzeug zum Verschieben der Messvorrichtung (1) in axialer Richtung und zum Verdrehen der Schraubeinrichtung (15) ansetzbar ist, und dass am äusseren Ende der Schraubspindel (13) wenigstens eine plane Angriffsfläche (14) vorgesehen ist, die das Ansetzen eines Hilfswerkzeuges zum Fixieren der Drehwinkellage der Schraubspindel und damit des Wandlers ermöglicht.18. Measuring device according to one of the preceding claims, characterized in that the screwing device (15) has a coaxial cylindrical projection (18) which projects beyond the outer axial bearing (17) of the screwing device and which carries a radial pin (19) to which a Auxiliary tool for moving the measuring device (1) in the axial direction and for rotating the screwing device (15) can be used, and that at the outer end of the screwing spindle (13) at least one flat engagement surface (14) is provided, which allows the attachment of an auxiliary tool for fixing the Angle of rotation of the screw spindle and thus of the converter enables. 19. Messvorrichtung nach einem der vorhergehenden Ansprüche dadurch gekennzeichnet, dass die Hülse (24) an ihrem dem Innenkonus (25) abgewandten Ende Mittel, z.B. einen radialen Zapfen (27) aufweist, an denen ein Hilfswerkzeug zum Verschieben der Messvorrichtung (23) in axialer Richtung und zum Fixieren der Drehwinkellage des Wandlers (6) ansetzbar ist, wobei die Schraubspindel (13) gegen ein Verdrehen gegenüber der Hülse (24) gesichert ist, und dass an der Schraubeinrichtung (15) wenigstens eine plane Angriffsfläche (20) vorgesehen ist, die das Ansetzen eines Hilfswerkzeuges zum Verdrehen der Schraubeinrichtung ermöglicht.19. Measuring device according to one of the preceding claims, characterized in that the sleeve (24) on its end facing away from the inner cone (25) means, e.g. has a radial pin (27) on which an auxiliary tool for displacing the measuring device (23) in the axial direction and for fixing the angular position of the transducer (6) can be attached, the screw spindle (13) preventing rotation relative to the sleeve (24) is secured, and that at least one flat engagement surface (20) is provided on the screwing device (15), which enables the attachment of an auxiliary tool for rotating the screwing device. 20. Messvorrichtung nach einem der vorhergehenden Ansprüche dadurch gekennzeichnet, dass die elektrischen Funktionen mindestens teilweise im Gehäuse (7) und/oder Ansatzrohr (8) integriert sind.20. Measuring device according to one of the preceding claims, characterized in that the electrical functions are at least partially integrated in the housing (7) and / or extension tube (8).
EP86112831A 1986-09-18 1986-09-18 Force-measuring device with an electromagnetic transducer Expired EP0260337B1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
DE8686112831T DE3664166D1 (en) 1986-09-18 1986-09-18 Force-measuring device with an electromagnetic transducer
EP86112831A EP0260337B1 (en) 1986-09-18 1986-09-18 Force-measuring device with an electromagnetic transducer
AT86112831T ATE44318T1 (en) 1986-09-18 1986-09-18 LOAD DEVICE WITH AN ELECTROMECHANICAL TRANSDUCER.
JP62199668A JPS6383627A (en) 1986-09-18 1987-08-10 Force measuring device
US07/098,206 US4800760A (en) 1986-09-18 1987-09-18 Force measuring device with an electromechanical transducer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP86112831A EP0260337B1 (en) 1986-09-18 1986-09-18 Force-measuring device with an electromagnetic transducer

Publications (2)

Publication Number Publication Date
EP0260337A1 true EP0260337A1 (en) 1988-03-23
EP0260337B1 EP0260337B1 (en) 1989-06-28

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EP86112831A Expired EP0260337B1 (en) 1986-09-18 1986-09-18 Force-measuring device with an electromagnetic transducer

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US (1) US4800760A (en)
EP (1) EP0260337B1 (en)
JP (1) JPS6383627A (en)
AT (1) ATE44318T1 (en)
DE (1) DE3664166D1 (en)

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DE10219430B4 (en) * 2002-05-02 2007-06-14 Audi Ag Device for axial bearing force measurement
EP2136192A1 (en) * 2008-06-17 2009-12-23 Hamilton Bonaduz AG Sensor fixing assembly

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DE19516643C1 (en) * 1995-05-05 1996-08-14 Wolfgang A Dr Hamm Highly accurate force and distance measuring head which determines broad range of physical properties
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DE102006003792B4 (en) * 2006-01-25 2013-11-14 Betriebsforschungsinstitut VDEh Institut für angewandte Forschung Gesellschaft mit beschränkter Haftung Holder for a pressure sensor and measuring roller with a pressure sensor
SE531268C8 (en) * 2007-04-19 2009-03-24 Skf Ab A combination of a load cell and a tubular insert to be mounted in a bore

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DE10219430B4 (en) * 2002-05-02 2007-06-14 Audi Ag Device for axial bearing force measurement
EP2136192A1 (en) * 2008-06-17 2009-12-23 Hamilton Bonaduz AG Sensor fixing assembly

Also Published As

Publication number Publication date
ATE44318T1 (en) 1989-07-15
JPS6383627A (en) 1988-04-14
EP0260337B1 (en) 1989-06-28
DE3664166D1 (en) 1989-08-03
US4800760A (en) 1989-01-31

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